Dangerous build problem while running I-PI simulation with LAMMPS as a client.

[AnuragKr]

Hello,

I tried to run an I-Pi simulation with LAMMPS as a client. Dataset obtained of liquid water at P = 1 bar and T = 300 K, at the PI-AIMD level. The initial input of water molecules for LAMMPS simulation taken from deepmd/examples.

Issue -- I was getting a very high number of dangerous builds and tried to reduce neighbor and neigh_modify value, but the still dangerous build is coming high. Is it normal for a dangerous build to have such high value for an I-PI simulation with Lammps as a client or there is some mistake with the methodology?

Will a dangerous build affect RDF values?

Total # of neighbors = 43060
Average neighs/atom = 224.27083
Neighbor list builds = 584746
Dangerous builds = 548086

LAMMPS Code --

# bulk water
units metal
atom_style atomic
boundary p p p
read_data water.lmp

neighbor        2 bin
neigh_modify    every 10 delay 0 check yes

mass 1 16
mass 2 1

pair_style deepmd ../240_25_viral/0.02_1_v/graph.pb
pair_coeff * *

timestep 0.00048

group Oatoms type 1
group Hatoms type 2

fix 1 all ipi localhost 8080 unix reset

thermo_style custom step temp ke pe etotal press vol
thermo 100
thermo_modify format line "%d %.6e %.6e %.6e %.6e %.6e %.6e %.6e %.6e %.6e"

dump my_dump all custom 100 lw_pimd.xyz id type x y z vx vy vz
dump_modify my_dump sort id
dump my_dump2 all atom 100 lw_pimd.lammps-dump-text

compute myRDF all rdf 100 1 1 1 2 2 2
fix 2 all ave/time 100 1 100 c_myRDF[*] file lw_pimd.rdf mode vector ave running

I-PI Code

<simulation verbosity='high'>
  <output prefix='simulation'>
    <properties stride='50' filename='out'>  [ step, time{picosecond}, conserved{electronvolt}, temperature{kelvin}, kinetic_cv{electronvolt}, potential{electronvolt}, pressure_cv{megapascal}, pressure_md{megapascal}, density{g/cm3} ] </properties>
    <!--trajectory filename='pos' stride='1'> positions </trajectory-->
    <trajectory stride='50' format='xyz' filename='pos'> positions{angstrom} </trajectory>
    <checkpoint stride='200'/>
  </output>
  <total_steps>625000</total_steps>
  <prng>
    <seed>31415</seed>
  </prng>
  <ffsocket name='lammps' mode='unix'>
    <address>localhost</address>
    <latency>0.001</latency>
    <port>8080</port>
  </ffsocket>
  <system>
    <initialize nbeads='8'>
      <file mode='xyz'> conf.xyz </file>
      <velocities mode='thermal' units='kelvin'> 300 </velocities>
    </initialize>
    <forces>
      <force forcefield='lammps'> </force>
    </forces>
    <motion mode='dynamics'>
      <dynamics mode='npt'>
       <timestep units='femtosecond'> 0.48 </timestep>
       <barostat mode='isotropic'>
        <thermostat mode='gle'>
          <A shape='(5,5)'>
            [   1.119252684345e-2,    8.975945537096e-6,   -2.728650447177e-5,   -7.011051989908e-4,    8.414373543550e-3,
          1.194065829660e-7,    1.071876106695e-6,   -9.439643019253e-6,   -1.329262116026e-5,   -2.667325152958e-6,
          2.161979961890e-4,    9.439643019253e-6,    4.639122293442e-5,    4.329184279724e-6,    8.132076333400e-5,
         -7.322257663569e-4,    1.329262116026e-5,   -4.329184279724e-6,    5.173717780694e-4,    1.590872642196e-5,
          8.299189140989e-3,    2.667325152958e-6,   -8.132076333400e-5,   -1.590872642196e-5,    6.992095202254e-3
           ]
          </A>
        </thermostat>
 <tau units='femtosecond'> 1000 </tau>
       </barostat>
       <thermostat mode='gle'>
          <A shape='(5,5)'>
            [   1.119252684345e-2,    8.975945537096e-6,   -2.728650447177e-5,   -7.011051989908e-4,    8.414373543550e-3,
          1.194065829660e-7,    1.071876106695e-6,   -9.439643019253e-6,   -1.329262116026e-5,   -2.667325152958e-6,
          2.161979961890e-4,    9.439643019253e-6,    4.639122293442e-5,    4.329184279724e-6,    8.132076333400e-5,
         -7.322257663569e-4,    1.329262116026e-5,   -4.329184279724e-6,    5.173717780694e-4,    1.590872642196e-5,
          8.299189140989e-3,    2.667325152958e-6,   -8.132076333400e-5,   -1.590872642196e-5,    6.992095202254e-3
           ]
          </A>
       </thermostat>
      </dynamics>
    </motion>
    <ensemble>
      <temperature units='kelvin'> 300 </temperature>
      <pressure units='megapascal'> 0.1 </pressure>
    </ensemble>
  </system>
</simulation>